Linux Virtualization - Mar 2020 - [PATCH 28/51] drm/bochs: Drop explicit drm_mode_config_cleanup

Instead rely on the automatic clean, for which we just need to check
that drm_mode_config_init succeeded. To avoid an inversion in the
cleanup we also have to move the dev_private allocation over to
drmm_kzalloc.

This is made possible by a preceeding patch which added a drmm_
cleanup action to drm_mode_config_init(), hence all we need to do to
ensure that drm_mode_config_cleanup() is run on final drm_device
cleanup is check the new error code for _init().

v2: Explain why this cleanup is possible (Laurent).

v3: Use drmm_mode_config_init() for more clarity (Sam, Thomas)

Cc: Sam Ravnborg <sam at ravnborg.org>
Cc: Thomas Zimmermann <tzimmermann at suse.de>
Cc: Laurent Pinchart <laurent.pinchart at ideasonboard.com>
Signed-off-by: Daniel Vetter <daniel.vetter at intel.com>
Cc: Gerd Hoffmann <kraxel at redhat.com>
Cc: virtualization at lists.linux-foundation.org
---
 drivers/gpu/drm/bochs/bochs.h     |  1 -
 drivers/gpu/drm/bochs/bochs_drv.c |  6 ++----
 drivers/gpu/drm/bochs/bochs_kms.c | 14 +++++---------
 3 files changed, 7 insertions(+), 14 deletions(-)

diff --git a/drivers/gpu/drm/bochs/bochs.h b/drivers/gpu/drm/bochs/bochs.h
index 917767173ee6..e5bd1d517a18 100644
--- a/drivers/gpu/drm/bochs/bochs.h
+++ b/drivers/gpu/drm/bochs/bochs.h
@@ -92,7 +92,6 @@ void bochs_mm_fini(struct bochs_device *bochs);
 
 /* bochs_kms.c */
 int bochs_kms_init(struct bochs_device *bochs);
-void bochs_kms_fini(struct bochs_device *bochs);
 
 /* bochs_fbdev.c */
 extern const struct drm_mode_config_funcs bochs_mode_funcs;
diff --git a/drivers/gpu/drm/bochs/bochs_drv.c
b/drivers/gpu/drm/bochs/bochs_drv.c
index addb0568c1af..e18c51de1196 100644
--- a/drivers/gpu/drm/bochs/bochs_drv.c
+++ b/drivers/gpu/drm/bochs/bochs_drv.c
@@ -7,6 +7,7 @@
 
 #include <drm/drm_drv.h>
 #include <drm/drm_atomic_helper.h>
+#include <drm/drm_managed.h>
 
 #include "bochs.h"
 
@@ -21,10 +22,7 @@ static void bochs_unload(struct drm_device *dev)
 {
 	struct bochs_device *bochs = dev->dev_private;
 
-	bochs_kms_fini(bochs);
 	bochs_mm_fini(bochs);
-	kfree(bochs);
-	dev->dev_private = NULL;
 }
 
 static int bochs_load(struct drm_device *dev)
@@ -32,7 +30,7 @@ static int bochs_load(struct drm_device *dev)
 	struct bochs_device *bochs;
 	int ret;
 
-	bochs = kzalloc(sizeof(*bochs), GFP_KERNEL);
+	bochs = drmm_kzalloc(dev, sizeof(*bochs), GFP_KERNEL);
 	if (bochs == NULL)
 		return -ENOMEM;
 	dev->dev_private = bochs;
diff --git a/drivers/gpu/drm/bochs/bochs_kms.c
b/drivers/gpu/drm/bochs/bochs_kms.c
index e8cc8156d773..7f4bcfad87e9 100644
--- a/drivers/gpu/drm/bochs/bochs_kms.c
+++ b/drivers/gpu/drm/bochs/bochs_kms.c
@@ -134,7 +134,11 @@ const struct drm_mode_config_funcs bochs_mode_funcs = {
 
 int bochs_kms_init(struct bochs_device *bochs)
 {
-	drm_mode_config_init(bochs->dev);
+	int ret;
+
+	ret = drmm_mode_config_init(bochs->dev);
+	if (ret)
+		return ret;
 
 	bochs->dev->mode_config.max_width = 8192;
 	bochs->dev->mode_config.max_height = 8192;
@@ -160,11 +164,3 @@ int bochs_kms_init(struct bochs_device *bochs)
 
 	return 0;
 }
-
-void bochs_kms_fini(struct bochs_device *bochs)
-{
-	if (!bochs->dev->mode_config.num_connector)
-		return;
-
-	drm_mode_config_cleanup(bochs->dev);
-}
-- 
2.24.1

On Mon, Mar 02, 2020 at 11:26:08PM +0100, Daniel Vetter
wrote:
> Instead rely on the automatic clean, for which we just need to check
> that drm_mode_config_init succeeded. To avoid an inversion in the
> cleanup we also have to move the dev_private allocation over to
> drmm_kzalloc.
> 
> This is made possible by a preceeding patch which added a drmm_
> cleanup action to drm_mode_config_init(), hence all we need to do to
> ensure that drm_mode_config_cleanup() is run on final drm_device
> cleanup is check the new error code for _init().
Acked-by: Gerd Hoffmann <kraxel at redhat.com>

On Mon, Mar 02, 2020 at 11:26:08PM +0100, Daniel Vetter
wrote:
> Instead rely on the automatic clean, for which we just need to check
> that drm_mode_config_init succeeded. To avoid an inversion in the
> cleanup we also have to move the dev_private allocation over to
> drmm_kzalloc.
> 
> This is made possible by a preceeding patch which added a drmm_
> cleanup action to drm_mode_config_init(), hence all we need to do to
> ensure that drm_mode_config_cleanup() is run on final drm_device
> cleanup is check the new error code for _init().
> 
> v2: Explain why this cleanup is possible (Laurent).
> 
> v3: Use drmm_mode_config_init() for more clarity (Sam, Thomas)
> 
> Cc: Sam Ravnborg <sam at ravnborg.org>
> Cc: Thomas Zimmermann <tzimmermann at suse.de>
> Cc: Laurent Pinchart <laurent.pinchart at ideasonboard.com>
> Signed-off-by: Daniel Vetter <daniel.vetter at intel.com>
> Cc: Gerd Hoffmann <kraxel at redhat.com>
> Cc: virtualization at lists.linux-foundation.org
Acked-by: Sam Ravnborg <sam at ravnborg.org>

> ---
>  drivers/gpu/drm/bochs/bochs.h     |  1 -
>  drivers/gpu/drm/bochs/bochs_drv.c |  6 ++----
>  drivers/gpu/drm/bochs/bochs_kms.c | 14 +++++---------
>  3 files changed, 7 insertions(+), 14 deletions(-)
> 
> diff --git a/drivers/gpu/drm/bochs/bochs.h b/drivers/gpu/drm/bochs/bochs.h
> index 917767173ee6..e5bd1d517a18 100644
> --- a/drivers/gpu/drm/bochs/bochs.h
> +++ b/drivers/gpu/drm/bochs/bochs.h
> @@ -92,7 +92,6 @@ void bochs_mm_fini(struct bochs_device *bochs);
>  
>  /* bochs_kms.c */
>  int bochs_kms_init(struct bochs_device *bochs);
> -void bochs_kms_fini(struct bochs_device *bochs);
>  
>  /* bochs_fbdev.c */
>  extern const struct drm_mode_config_funcs bochs_mode_funcs;
> diff --git a/drivers/gpu/drm/bochs/bochs_drv.c
b/drivers/gpu/drm/bochs/bochs_drv.c
> index addb0568c1af..e18c51de1196 100644
> --- a/drivers/gpu/drm/bochs/bochs_drv.c
> +++ b/drivers/gpu/drm/bochs/bochs_drv.c
> @@ -7,6 +7,7 @@
>  
>  #include <drm/drm_drv.h>
>  #include <drm/drm_atomic_helper.h>
> +#include <drm/drm_managed.h>
>  
>  #include "bochs.h"
>  
> @@ -21,10 +22,7 @@ static void bochs_unload(struct drm_device *dev)
>  {
>  	struct bochs_device *bochs = dev->dev_private;
>  
> -	bochs_kms_fini(bochs);
>  	bochs_mm_fini(bochs);
> -	kfree(bochs);
> -	dev->dev_private = NULL;
>  }
>  
>  static int bochs_load(struct drm_device *dev)
> @@ -32,7 +30,7 @@ static int bochs_load(struct drm_device *dev)
>  	struct bochs_device *bochs;
>  	int ret;
>  
> -	bochs = kzalloc(sizeof(*bochs), GFP_KERNEL);
> +	bochs = drmm_kzalloc(dev, sizeof(*bochs), GFP_KERNEL);
>  	if (bochs == NULL)
>  		return -ENOMEM;
>  	dev->dev_private = bochs;
> diff --git a/drivers/gpu/drm/bochs/bochs_kms.c
b/drivers/gpu/drm/bochs/bochs_kms.c
> index e8cc8156d773..7f4bcfad87e9 100644
> --- a/drivers/gpu/drm/bochs/bochs_kms.c
> +++ b/drivers/gpu/drm/bochs/bochs_kms.c
> @@ -134,7 +134,11 @@ const struct drm_mode_config_funcs bochs_mode_funcs =
{
>  
>  int bochs_kms_init(struct bochs_device *bochs)
>  {
> -	drm_mode_config_init(bochs->dev);
> +	int ret;
> +
> +	ret = drmm_mode_config_init(bochs->dev);
> +	if (ret)
> +		return ret;
>  
>  	bochs->dev->mode_config.max_width = 8192;
>  	bochs->dev->mode_config.max_height = 8192;
> @@ -160,11 +164,3 @@ int bochs_kms_init(struct bochs_device *bochs)
>  
>  	return 0;
>  }
> -
> -void bochs_kms_fini(struct bochs_device *bochs)
> -{
> -	if (!bochs->dev->mode_config.num_connector)
> -		return;
> -
> -	drm_mode_config_cleanup(bochs->dev);
> -}
> -- 
> 2.24.1